1. A manufacture method of an optical sheet made of a transparent thermoplastic resin sheet as a surface thereof a regular geometric design working is performed, the optical sheet manufacture method comprising:
performing a geometric design working on the resin sheet at a temperature not lower than a glass transition temperature of the resin sheet, by using a metal endless working belt formed with a geometric design on a surface thereof;
rapidly cooling the resin sheet on which the geometric design working is performed to a temperature lower than the glass transition temperature; and
detaching the rapidly cooled resin sheet from the metal endless working belt.
2. The optical sheet manufacture method according to claim 1, wherein the resin sheet is made of transparent crystalline resin.
3. The optical sheet manufacture method according to claim 2, wherein the resin sheet is made of PET. PEN, or mixture or copolymer of PE-T and PEN.
4. The optical sheet manufacture method according to claim 1, wherein the temperature not lower than a glass transition temperature is not lower than Tg+60\xb0 C. and not higher than Tg+90\xb0 C., where Tg (\xb0 C.) is the glass transition temperature of the resin sheet.
5. The optical sheet manufacture method according to claim 1, wherein the resin sheet is cooled at a cooling speed not slower then 5\xb0 C.sec and not higher then 40\xb0 C.sec in the step of rapidly cooling the resin sheet.
6. The optical sheet manufacture method according to claim 1, wherein the resin sheet has a crystallization rate of 20% or less when the resin sheet is detached from the metal endless working belt.
7. The optical sheet manufacture method according to claim 1, wherein an increase of a crystallization rate of the resin sheet is 5% or less before and after performing the optical sheet manufacture method.
8. The optical sheet manufacture method according to claim 1, wherein a plurality of resin sheets are inputted, and the plurality of resin sheets are thermally bonded and integrated while a shape is transferred by the metal endless working belt.
9. The optical sheet manufacture method according to claim 1, wherein a total thickness of the resin sheet is 500 \u03bcm or thinner.
10. The optical sheet manufacture method according to claim 1, wherein a ratio of a height of a transferred portion to a total thickness of the resin sheet is 90% or less.
11. The optical sheet manufacture method according to claim 1, wherein the geometric design transferred to the resin sheet is an emboss shape.
12. The optical sheet manufacture method according to claim 11, wherein the emboss shape transferred to the resin sheet is a prism shape.
13. The optical sheet manufacture method according to claim 12, wherein the prism shape transferred to the resin sheet is an isosceles triangle having an apex angle of 90\xb0.
14. The optical sheet manufacture method according to claim 13, wherein a transfer rate of the prism shape to the resin sheet is 98% or higher.
15. The optical sheet manufacture method according to claim 1, wherein the metal endless working belt is wound around a heating roll set to a temperature higher than the glass transition temperature of the resin sheet and around a cooling roll set to a temperature lower than the glass transition temperature of the resin sheet, and transferred in synchronization with rotation of the heating roll and the cooling roll.
16. The optical sheet manufacture method according to claim 15, wherein;
the resin sheet is processed between a nip roll disposed in a manner it faces the heating roll and the metal endless working belt; and
a nip line pressure between the metal endless working belt and the nip roll is not lower than 5 kgcm and not higher than 30 kgcm.
17. The optical sheet manufacture method according to claim 16, wherein;
an endless belt is wound around the nip roll and around an opposing roll facing the cooling roll; and
the resin sheet is transferred with being sandwiched and held between the metal endless working belt and the endless belt.
18. The optical sheet manufacture method according to claim 17, wherein while a shape is transferred to the resin sheet by the metal endless working belt, a shape is also transferred to an opposite side of the resin sheet by a geometric shape formed on a surface of the endless belt.
19. The optical sheet manufacture method according to claim 1, wherein the geometric design worked on the surface of the resin sheet has at least one corner.
20. The optical sheet manufacture method according to claim 1, wherein;
a roll temperature of a heating roll for transferring the resin sheet is set to be high in a central portion compared with the roll temperature in opposite end portions; and
a roll temperature of a cooling roll for transferring the resin sheet is set low in a central portion compared with the roll temperature in opposite end portions.
21. An optical sheet manufactured by the optical sheet manufacture method recited in claim 1, wherein the optical sheet is used as a prism sheet disposed between a liquid crystal display panel and a light source for illuminating the liquid crystal display panel.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An optical image recording system for electronic recording of optical information, said optical image recording system comprising
a lens system (21,22,23), and a body (20);
said body having a configuration with a low height (b) and with broad surfaces (201,202) through one of which broad surfaces said optical information is being received, and said body accommodating an image recording device (25) having a light sensitive area, a memory, and means for transferring and receiving electronic signals;
CHARACTERIZED in
that said lens system is accomodated in said body;
that said lens system comprises: a front lens group (21) having a first optical axis (211), a back lens group (22) consisting of one or more lenses having a second optical axis (221), and a reflective element (23) folding the first optical axis (211) into the second optical axis (221) in an angle (a) of less than 180 degrees; and
that said lens system has a ratio (S) of the optical system height (H) divided by the diameter (D) of the circumferential circle of the formed image (28) less than 4, said optical system height (H) being the maximum projected distance on the first optical axis from any part of the optical system including lenses, filters, aperture stop, image recoding device and the body thereof;
and that said body has a height (b) so that said optical image recording system can be accomodated in a compact, flat camera which can be kept in a wallet or a small handbag designed for carrying credit cards.
2. A system according to claim 1, wherein the lens system comprises an additional reflective element (24) folding the second optical axis (221) into the optical axis (251) of the image recording device.
3. A system according to claim 1; wherein the first optical axis (211) and the second optical axis (221) form an angle (a) equal to or less than 90 degrees.
4. A system according to claim 1; wherein the second optical axis (221) and the optical axis (251) of the image recording device form an angle equal to or less than 90 degrees.
5. A system according to claim 1; wherein the first optical axis (211) and the optical axis (251) of the image recording device are substantially in the same plane.
6. A system according to claim 1, wherein the first optical axis (211) and the optical axis (251) of the image recording device are substantially parallel.
7. A system according to claim 1, wherein the image recording device is a charge coupled device.
8. A system according to claim 1, wherein the lens system has a ratio (S) of the optical system height (H) divided by the diameter (D) of the circumferential circle of the formed image (28) equal to or less than 2.55, more preferred equal to or less than 1.7, most preferred less than 1.2.
9. A system according to claim 1, wherein the height ratio of the effective lens height (h) and the effective focal length (f) of the lens system is less than 1.7, preferably less than 1.5.
10. A system according to claim 1, wherein the height of said body is less than 20 mm, preferably less than or equal to 10.5 mm, more preferably less than or equal to 7 mm, most preferably less than or equal to 5 mm.
11. A system according to claim 1, wherein the front lens group (21) and the first reflective element (23) consist of a prism.
12. A system according to claim 1, wherein the additional reflective element (24) consist of a prism.
13. A system according to claim 1, wherein the aperture stop of the lens system is determined by a stop (26) placed after the first reflective element, particularly placed in the back lens group (22).
14. A system according to claim 1, wherein said body further comprises means for storing, transferring and receiving electronic signals of other information than optical information to and from an external device.
15. A system according to claim 14, wherein the means for transferring and receiving electronic signals comprises a connector device (1001) having a databus interface.
16. A system according to claim 15, wherein the connector device is accommodated in an end face of said body.
17. A system according to claim 14, wherein the storage means for storing the electronic signals consist of an exchangeable memory (1002).
18. A system according to claim 1, wherein the body further comprises means for storing electronic signals of control information for controlling the operation of the external device.
19. A system according to claim 18, which comprises means for loading the control information into the external device.
20. A system according to claim 14, wherein the means for transferring electronic signals comprise a wireless transmitter of analogue andor digital transmission.
21. A system according to claim 14, wherein the means for receiving electronic signals comprise a wireless receiver of analogue andor digital transmission.
22. A system according to claim 1, wherein said body further comprises guiding means for its guidance in a slot.
23. An optical image recording and processing system for recording and processing of electrical signals of optical information and other information; said system comprising an optical image recording system according to claim 1; wherein said means for transferring and receiving electronic signals consist of a pair of connector devices (1001,1301) having a databus interface, wherein one connector device (1001) of said pair of connector devices is accommodated in the optical image recording system for direct connection to the other of said pair of connector devices (1301) accommodated in the image processing system.
24. A system according to claim 23, wherein the connector device of the optical image recording system is accommodated in the end face thereof.
25. A system according to claim 23, wherein the image processing system accommodates the connector device (1301) in a slot (1102).
26. A system according to claim 23, wherein the optical image recording system and the processing system comprise guiding means (1004,1101) for guiding their mutual connection.